In my experience the muscle groups with long muscle bellies and short tendons grow the fastest when trained frequently and intensely. Those, however, vary for different people. As I wrote in the article about calves some people will never be able to develop that muscle group to something impressive, regardless of training, food intake or drug usage because when the insertions are really high there is not much muscle to grow in the first place. You should probably still train your calves though, at least for strength and ankle health. Ultimately, it’s up to you.
You will notice that the muscle groups that are the fullest to begin with will respond quickly to training because they contain more muscle fibers, which gives them higher growth potential Those muscle groups are also easier to activate during compound exercises.
Of course, you have to keep in mind that I am not talking about some incredible muscle size. After all, natural bodybuilding comes with its strong limitations.
At the end of the day, it’s all about your personal genetics. For example, my latissimus dorsi muscles have really low insertions which makes training lats a joy. However, my calves, forearms, hamstrings and arms have ridiculously short muscle bellies, and I know very well that those won’t improve much regardless of training routines and experts’ advices.
Since people are different, I can’t tell you exactly which will be the fastest muscle to grow on you. In general, the longer the muscle, the better as far as bodybuilding/recreational muscle building is concerned. If you have nice long biceps, those will grow quite easily compared to other less favorable body parts. When the muscle is lengthy there is just more room for growth and nothing can change that – not even steroids.
You will notice that most professional bodybuilders struggle with this and curse their genetics too. For example, look at Branch Warren’s forearms compared to the rest of him. They are underdeveloped because of the poor insertions. Not that forearms will help him look any better.
There are many more examples too. The bodybuilder Dennis Wolf has really high lat insertions which create the appearance of weak and naked lower back. On the other hand guys like Joel Stubbs, Larry Scott, Dorian Yates have really low lats which make their backs wider and thicker looking.
That’s also the reason why Phil Heath looks more “aesthetically pleasing” /what a term that one is/ than almost everybody else. He has full muscle bellies in his entire body and thus no underdeveloped parts. He does not have any major weaknesses.
I hate using professional bodybuilders for examples, because people tend to get the wrong idea, but since those guys are famous it’s very easy to illustrate my point.
Muscle groups that are more likely to have shorter muscle bellies (it all depends on the person at the end of the day)
Calves – high calves are often found on many people who have long legs, but it’s not a guarantee by any means. You can be tall and still have long calves.
Biceps & Triceps
HOW YOU TRAIN IN THE BEGINNING MATTERS MORE THAN YOU THINK
You can only build so much muscle naturally and that’s why you should choose wisely how to spend your credit. Everybody knows somebody who used to train arms and torso all day everyday and now has underdeveloped legs. Usually for those people the lower body remains on the weak side forever. This also explains why all of those “Do you want to be a centaur?” 5×5 squat routines produce so many people with good legs and hips but weak upper bodies. Of course, the centaur look is linked to high body fat too. Many people who follow the centaur path tend to get fat as hell, and the legs are a good place to store fat. This could give the illusion of bigger lower body, when in fact there is not that much actual muscle.
I believe the way you train in the beginning always leaves a mark on how you look for the rest of your life.
UNIVERSAL MUSCLE GROUPS THAT GROW FAST
I have to say that the trapezius is a muscle that could grow relatively fast for most people. It’s a tough muscle, full of androgenic receptors and with very favorable insertions for heavy and frequent training. It also has very good blood supply. Over-training the traps is hard, although not impossible.
In addition, you will rarely see a bodybuilder with weak traps on professional stage. That’s because anabolic steroids make the traps explode right away.
EXERCISE FORM AND SELECTION MATTERS TOO
Your body is essentially a bio-machine. It’s designed to work in a certain way. While the basic functions are the same for every human being, your proportions determine which muscle works harder during certain exercises.
For example, the squat sucks big time for people with exceptionally long femurs. Whatever the experts say, that’s a fact of life. Long legs and short torso make the back squat a hip/glutes/lower back exercise. Therefore, you may be thinking that your legs cannot grow because of genetics, while the actual culprit is improper exercise choice.
There are usually two groups of people when it comes to the upper body – arms or torso dominant. The torso dominant lifters usually have a built that makes the chest and back do more work during compound exercises. As a result those groups usually develop faster and to larger proportions. Once again, I am not talking about enormous size here. Just a few extra grams of muscle. The torso guys are mostly taller people with long skinny arms.
On the other hand, people with long and dominant biceps and triceps can use those as bullies during push and pull movements. Those lifters are usually part of the T-rex arms crew. At least, those are my observations.
Muscle groups with short muscle bellies have less potential to grow, if any.
Tall people with longer limbs usually have more body parts with longer tendons, but there are exceptions too. This is not written in stone.
The traps have potential to grow because they allow for frequent heavy training.
The calves, forearms and hamstrings could be very stubborn body parts.
There is no need to overthink this because ultimately there is nothing that can be done. It’s good to know your limitations, but that’s it. It’s time for the next chapter cause this one is over for good.